Photographic polyester film base with subbing layer containing phosphoric acid derivative

摘要

Provided is a method of preparing film base material consisting of biaxially oriented synthetic linear polyester which comprises stretching extruded synthetic polyester material in one direction and then coating on this material a copolymer in form of an aqueous latex of vinylidene chloride, a plasticising comonomer for the vinylidene chloride and optionally other comonomers together with 10 to 40 percent by weight of solids in the latex of at least one phosphoric acid derivative of the formula <IMAGE> wherein M is hydrogen, ammonium or an alkali metal, R is methyl, ethyl or an ethylene oxide and/or propylene oxide units containing group, and R1 is hydrogen, methyl or ethyl, drying this coating and completing the orientation of the polyester film material. A photographic silver halide emulsion can be coated directly on this base without the need to apply any intermediate gelatin subbing layer. The adhesion between the film base and the photographic emulsion layers is improved and further the separation or frilling of these layers when the final photographic film is processed can be avoided. Due to the also improved surface conductivity of the film base there is no need for a separate antistatic layer.